Related Experiment Videos
Telomerase activity during carcinogenesis in the bronchus
Masatoshi Kakihana1, Naoyuki Yahata, Takashi Hirano
1First Department of Surgery, Tokyo Medical University School of Medicine, Shinjuku-ku, Tokyo 160-0023, Japan. kaki1967@xa2.so-net.ne.jp
Oncology Reports
|December 19, 2001
Summary
Telomerase activity, detected by the telomerase activity assay (TRAP), was absent in precancerous bronchial lesions but present in most lung cancers. This suggests telomerase activation is a late event in bronchial carcinogenesis.
Area of Science:
- Oncology
- Molecular Biology
- Pulmonology
Background:
- Telomerase synthesizes telomeric DNA and is typically absent in normal cells.
- Bronchial squamous cell carcinomas may develop through metaplasia and dysplasia.
- The telomerase activity assay (TRAP) is a sensitive method for detecting telomerase.
Purpose of the Study:
- To investigate telomerase RNA levels in precancerous bronchial lesions.
- To determine if telomerase activity increases during bronchial carcinogenesis.
Main Methods:
- Bronchial-brushing extracts were analyzed using fluorescence-based TRAP (F-TRAP) and in situ TRAP assays.
- Telomerase activity was compared with cytological features.
Main Results:
- Telomerase activity was detected in 66.7% of lung cancer cases (8/12), including 66.7% of squamous cell carcinomas (6/9).
- No telomerase activity was detected in normal or precancerous bronchial lesions using either F-TRAP or in situ TRAP.
Conclusions:
- Dysplastic bronchial cells may not possess immortalizing properties.
- Increased telomerase activity appears to be a late-stage event in bronchial carcinogenesis.
- Measuring telomerase activity may aid in distinguishing between dysplasia and in situ carcinoma, offering clinical value for treatment decisions.